- Jun 5, 2015
- Reaction score
I have a couple questions for anyone that has built the little River Queen Launch engine. The first one concerns the crank disc. The drawing calls for a diameter of 3/4" and the pin to be offset by 5/16". This leaves barely enough material to drill a tap size hole for the 6-32 threads, and when the tap is run through it cuts through the outer surface. .375" minus .3125" only leaves .0625", a #36 drill is .106", and that only leaves .0095". I'm planning to make one more 7/8" diameter and adjust if need be, but it looks like there is plenty of room. I'm just curious what others have done here. Next is the precise location and timing of the intake and exhaust grooves of the rotary valve. I suppose I can figure it out when I get farther along. It just seems that the drawing and description of the operation is a little vague. I should say that the rotary valve in Rudy's Radial 5 caused me to doubt my ability to figure it out as well until I actually did it. So maybe that's all I really need to do.